SE2051471A1

SE2051471A1 - Sealing device

Info

Publication number: SE2051471A1
Application number: SE2051471A
Authority: SE
Inventors: Erik Lans
Original assignee: Camfil Ab
Priority date: 2020-12-16
Filing date: 2020-12-16
Publication date: 2022-06-17
Also published as: SE544656C2; WO2022131989A1

Abstract

A sealing device (1) comprising a gasket (5) configured to seal a gap (2) between a first element (3) and a second element (4), wherein the gasket is arranged to be located in the gap (2) and to be in contact with the first and the second elements (3,4) during use, the sealing device comprising: a gasket (5) comprising two elongated gasket members (5a, 5b), where an inner elongated gasket member (5a) is configured to surround an area (A), and an outer elongated gasket member (5b) is configured to surround the inner gasket (5a) and said area (A); and a carrier member (6), extending along the length of the elongated gasket members (5a, 5b) , and said elongated gasket members (5a, 5b) being attached to the carrier member so that they are held in position on a distance from each other so as to form an intermediate gasket space (8) between the gasket members (5a, 5b); and a channel (7) connecting the intermediate gasket space (8) with the surroundings and being configured to be connected to a pressure source, to allow application of pressure on the intermediate gasket space (8) during use.

Description

SEALING DEVICE TECHNICAL FIELD The present disclosure relates to sealing device configured to seal a gap between a first and a second element, one of said elements preferably being a filter frame.

BACKGROUND ART ln situations where it is necessary to seal off an interior space from the outside, gasketsare commonly used to seal off gaps between structures that enclose such an interior space toprevent passage of unwanted substances such as particles, fluids, gas or other contaminantsthrough the gap. The gasket can thereby serve to keep the interior space clean, or to preventunwanted substances from escaping from the interior space. ln cases where the sealed offinterior space contains equipment and/or substances which are particularly sensitive tocontaminants, or contains substances which are hazardous and cannot be allowed to escapeinto the surrounding environment, it is especially important to ensure that the sealing issufficiently leak tight. lt is also important to ensure that the sealing does not becomecompromised, and thus it necessary to regularly check the sealing tightness of the gasket, to beable to detect any leakage. Standard methods for leakage detection are available, for exampleas described in e.g. ISO 10648-2, EN12237 or EN1886. ln order to properly monitor leaktightness, it is important to provide the equipment with a sealing device allowing this. There isalso a need of a sealing device that can be applied to equipment not originally designed for leak tightness monitoring.

SUMMARY The present disclosure thus relates to sealing a gap between structural elements, and toprovide a sealing device, which can provide improved leak tightness and allow monitoring ofleak tightness to ensure that the sealing is always under control, in particular within air filtration.The present disclosure further aims at providing a sealing device by means of which existing equipment can be upgraded.

Accordingly, the present disclosure relates to a sealing device comprising a gasketconfigured to seal a gap between a first element and a second element, wherein the gasket is arranged to be located in the gap and to be in contact with the first and the second elements 2 during use. The sealing device comprises a gasket comprising two elongated gasket members,where an inner elongated gasket member is configured to surround an area, and an outerelongated gasket member is configured to surround the inner gasket and the area ; and a carriermember, extending along the length of the elongated gasket members, and the elongatedgasket members being attached to the carrier member so that they are held in position on adistance from each other so as to form an intermediate gasket space between the gasketmembers, and a channel connecting the intermediate gasket space with the surroundings andbeing configured to be connected to a pressure source, to allow application of pressure on theintermediate gasket space during use, and enabling connection of the sealing device to a of leaktightness monitoring system if desired. The first element is preferably a filter frame of an air filter and the second element is preferably a filter housing.

The carrier member may be a frame having a first surface and a second surface, saidsecond surface being opposite to said first surface, and said first and second surfaces extendingbetween the two elongated gasket members, whereby a first intermediate gasket space ispartially confined by said first surface, and a second intermediate gasket space is partiallyconfined by said second surface. At least one of the two elongated gasket members may bedivided along its length, into an first gasket member portion and a second gasket memberportion, wherein the first gasket member portion is/are attached to the first surface of theframe, and the second gasket member portion is/are attached to the second surface of theframe, and wherein the frame extends beyond at least one pair of said first and second gasket member portions in a direction transverse to the length ofthe elongated gasket members.

Alternatively, the carrier member may be an open framework extending between theelongated gasket members, and the two elongated gasket members may then be attached tothe carrier member so that portions of the open framework are partially enclosed by the material of the two elongated gasket members.

The channel connecting the intermediate gasket space with the surroundings and beingconfigured to be connected to a pressure source can be arranged through one of the two elongated gasket members. |fthe carrier is a frame, the channel connecting the intermediate gasket space with thesurroundings and being configured to be connected to a pressure source can be arrangedthrough the frame. The frame can be a hollow structure having one or more inner openings arranged in said first and/or second surface and an outer opening arranged in a portion of the frame extending beyond the first and second gasket member portions, said outer opening being configured to be connected to a pressure source.

The present disclosure further relates to an air filtration apparatus comprising the abovesealing device, a filter frame, and a filter housing, wherein the sealing device is located in a gapbetween the filter frame and the filter housing so that the gasket members ofthe sealing deviceare in contact with the filter frame and the housing; and to an air filtration system comprisingan air filtration apparatus and a pressure source, which is connected to the intermediatespace(s) of the sealing device, said pressure source preferably being configured to maintain aset pressure difference towards the surroundings. The air filtration system may suitablycomprise a control sensor located between the pressure source and the surroundings, which control sensor may preferably being configured to communicate with an evaluation device.

The present disclosure also relates to a method of installing the above sealing device inthe air filtration system, the method comprising the steps of: positioning the sealing device inthe gap between the filterframe and the filter housing; mounting the filter frame to the housingso that the gasket members of the sealing device are in contact with the filter frame and thehousing; and connecting the channel to the pressure source to allow a pressure to be applied on the intermediate gasket space(s) of the sealing device.

The present disclosure will become apparent from the detailed description given below.The detailed description and specific examples disclose preferred embodiments of thedisclosure by way of illustration only. Those skilled in the art understand from guidance in thedetailed description that changes and modifications may be made within the scope of the disclosure.BRIEF DESCRIPTION OF THE DRAWINGS The features and advantages of the present disclosure will be more fully appreciated byreference to the following illustrative and non-limiting detailed description of exampleembodiments of the present disclosure, when taken in conjunction with the accompanying drawings.

Figures 1a-b are a cross-sectional views schematically illustrating embodiments of asealing device of the present disclosure;Figure 2a-c are cross-sectional views schematically illustrating embodiments of a sealing device ofthe present disclosure wherein the carrier is in the form of a frame; 4 Figure 3 is a cross-sectional view schematically illustrating another embodiment of asealing device wherein the carrier is in the form of a frame; Figure 4a shows a perspective view of a of a sealing device wherein the carrier is in theform of a frame; Figure 4b shows a perspective view of a part of a sealing device wherein the carrier is inthe form of a frame; Figure 5a shows a perspective view of a of a sealing device wherein the carrier is in theform of an open framework; Figure 5b shows a top view of a part of a sealing device wherein the carrier is in the formof an open framework; Figure 6 is a cross-sectional view schematically illustrating a filter mounted in a filterhousing and sea|ed by a sealing device of the present disclosure; Figure 7 shows schematically a leak tightness monitoring system that can be connected to the sealing device of the present disclosure.

DETAILED DESCRIPTION As mentioned above, the present disclosure relates to sealing of a gap between twostructural elements in order to improve leak tightness and to allow monitoring thereof. ln manysituations, it may be necessary to seal off the interior volume of an enclosure or a room fromthe surrounding environment. This disclosure particularly relates to a device, which isconfigured to seal a gap between structural elements that enclose such an interior volume, toprevent passage of unwanted substances such as particles, fluids, gas or other contaminantsthrough the gap, and to systems and methods related to that. The gasket serves to seal the gapto prevent any leakage through the gap. Thereby, the interior volume of the enclosure can bekept clean, which is important for example within the pharmaceutical industry or withinmanufacture of electrical components. Similarly, if the enclosure or room accommodates itemsor activities, which may release unwanted or hazardous substances, such as for example toxicor pathogenic substances, such substances can be prevented from escaping from the enclosure OI' FOOm.

The sealing device of the present disclosure thus comprises a gasket configured to seala gap between a first element and a second element, wherein the gasket is arranged to belocated in the gap and to be in contact with the first and the second elements during use. The first element may typically be a movable or replaceable pa rt, that is mounted to cover an access opening in an enclosure or room, such as for example a filter, or a hatch or door. The secondelement may typically be a structure against which the first element is held or mounted, such as for example a wall casing ofthe enclosure or room. lt may often be desired or necessary to provide fresh air to the sealed enclosure or room,or to vent out gases there from, also when the enclosure or room must be fully leak proof. lnsuch cases a filter can be mounted in an opening between the interior of the sealed volume andthe surrounding. Leakage between the filter and the adjacent structure, against which the filteris mounted, can of course not be accepted, and the gap between a filter frame holding the filterand the mounting structure or filter housing, is thus a position where the sealing device of thepresent disclosure may be of particular use. The filter may for example be of panel type, boxtype or V type and can have any of the filter classes E10, E11, E12, H13, H14, U15, U16, U17according to EN 1822 or being classified according to ISO 16890.

The sealing device comprises a gasket comprising two elongated gasket members, wherean inner elongated gasket member is configured to surround an area, and an outer elongatedgasket member is configured to surround the inner gasket and the area. The area may typicallybe an opening between two spaces or compartments, such as an inlet or outlet opening in aroom or enclosure. For example, if the first element which is to be sealed is a filter and thesecond element is a filter housing, the area surrounded by the elongated gasket members willbe the surface of the filter. Accordingly, the gasket encircles the opening and seals the gapbetween the first and second elements, so that the encircled area is sealed off from thesurrounding during use of the sealing device. By providing two elongated gasket memberssurrounding the opening to be sealed during use and being in contact with both the first andthe second element, the leak tightness is improved since there is both an inward and an outwardgasket member that contribute to the sealing, and since the surfaces of both the first and thesecond element are in contact with the gasket material of the elongated gaskets. The sealingdevice can thus be disposed between the first and second elements and seal the gap without any need ofgluing a sealing element to the first or second element.

The gasket is held by a carrier member, which extends along the length ofthe elongatedgasket members, thus also surrounding the area surrounded by the gaskets. The elongatedgasket members are attached to the carrier member so that they are held in position on adistance from each other and so that an intermediate gasket space is formed between thegasket members. This facilitates handling ofthe gasket prior to mounting in the gap, and when the sealing device is mounted and positioned between the first and second elements the 6 intermediate gasket space is confined partially also by the surfaces of the first and secondelements. Further, the provision of the double gasket forming an intermediate gasket space there between allows for monitoring of leak tightness as will be described in more detail below.

The carrier member may be a frame onto which the gasket members are attached. Theframe has opposing first and second surfaces, which extend between the two elongated gasketmembers. Thereby intermediate gasket spaces are formed between the gasket members onboth sides ofthe frame, which are partially confined by the gasket members and frame surfacebetween the gasket members, and which are separated from each other. Two separateintermediate gasket spaces allow separate leak tightness monitoring on each side of the frame.The frame is preferably made of a rigid or semi-rigid material, such as plastic material or metal,and can be a solid or hollow structure. The surface ofthe frame is suitably substantially flat andcontinuous between the elongated gasket members, so that the intermediate gasket spacesformed on each side of the frame are completely separated from each other. A carrier in the form of a frame provides a robust sealing device that is easy to handle.

The gasket members can be attached to the frame such that the sides of the frameextend partially into the gasket members, as shown schematically in Fig. 1. The frame might alsobe configured to have one or more portions protruding sideways so as to extend through the gasket member so as to be exposed on the outside ofthe gasket.

Alternatively, one or both ofthe two elongated gasket members may suitably be dividedalong its length, into a first gasket member portion and a second gasket member portion. Thefirst portion is then attached to the first surface of the frame, and the second portion is attachedto the second opposing surface of the frame. ln this case, the frame extends beyond the pair ofgasket member portions in a direction transverse to the length of the elongated gasket members, and is exposed outside the gasket members on one or both sides.

Alternatively, the carrier member can be an open framework extending between theelongated gasket members, and the two elongated gasket members may then be attached tothe carrier member so that portions of the open framework are partially enclosed by thematerial ofthe two elongated gasket members. ln this case, only one intermediate gasket spaceis formed between the gasket members, since the spaces on each side of the carrier areconnected by the openings in the open framework. The open framework is suitably made of arigid or semi-rigid material, such as plastic material or metal. The open framework can forexample be in the form of a trellis or a latticework, or can be a flat undulating or zig zag shaped structure. As the carrier is an open framework, there is only one intermediate gasket formed 7 between the elongated gasket members. A carrier in the form of a frame can be made very thin an flexible, and can be suitable for example in situations where the gap to be sealed is narrow.

The gasket can be any suitable gasket or seal that can be arranged as two elongatedmembers, leaving a space between them. For example, the gasket may be made of e.g. foamedpolyurethane, solid polyurethane potting, polyurethane gel, silicone gel, self-adhesive EPDMrubber (ethylene propylene diene monomer rubber), or self-adhesive neoprene. The gasketshould be dimensioned to ensure a sufficient seal in the gap between the surfaces of the firstand second elements where it is intended to be mounted, i.e. have a length corresponding tothe length of the gap to completely encircle the area to be sealed off by the gasket, and a height exceeding the height of the gap to such an extent that a proper seal is obtained.

The two elongated gasket members may typically be connected to the carrier at aconstant distance from each other, but alternatively the gasket members can be positioned atdifferent distances from each other if desired, depending on the dimensions of the intendedgap. The distance between the two elongated gasket members may preferably be 0.5 to 100mm, more preferably 2-90 mm, most preferably 5-50 mm. The height of the sealing device, i.e.the distance between the surfaces of the gasket members that will be in contact with the firstand the second elements during use may preferably be 0.5 to 50 mm, more preferably 1 to 40mm. The cross-sectional area ofthe intermediate gasket space may preferably be 0.25 to 5000mmz, more preferably 2-2000 mmz, when the sealing device is in use. The area to be sealed bythe sealing device, i.e. the area A surrounded by the gasket, can typically be 250x250 mm to 1300x1900 mm.

A channel is provided in the sealing device to connect the intermediate gasket spacewith the surroundings. The channel is configured to be connected to a pressure source, to allowapplication of pressure on the intermediate gasket space during use, as will be explained in thefollowing. The channel can be directed towards the area surrounded by the gasket, or towardthe side of the gasket facing away from this area. A channel directed toward the surroundedarea may be preferred since it may be easier to install, since the connection to a pressure sourcecan be obtained also when the structure to be sealed was not initially adapted to connecting the gasket to pressure.

The channel can be arranged through one of the two elongated gasket members, towardthe area surrounded by the gasket, or outward, away from the area surrounded by the gasket.lt can be in the form of a tube extending through the gasket or a cylinder disposed in the gasket so as to connect the intermediate gasket space with the surroundings. ln embodiments 8 including intermediate gasket spaces on each side of the frame channels can be arrangedthrough the gasket member portions separately connecting the two intermediate gasket spaces 'CO a pFeSSUFe SOUFCQ. lf the carrier is a frame as described above, the channel connecting the intermediategasket space with the surroundings and being configured to be connected to a pressure sourcecan be arranged through one of the two elongated gasket members or through the frame. |ftheframe is solid or substantially solid, the channel can be formed through the frame material, forexample by drilling, so as to have an inner opening arranged in the first and/or second surfacebetween the gasket members and an outer opening arranged in a portion of the frameextending beyond the first and second gasket member portions and being exposed on theoutside of the sealing device. lf the frame is a hollow structure, it can have one or more inneropenings arranged in the first and/or second surface between the gasket members and an outeropening arranged in a portion of the frame extending beyond the first and second gasketmember portions and being exposed on the outside of the sealing device. ln this case, the framein its entirety acts as a channel connecting the intermediate gasket spaces with the surrounding.Accordingly, the inner opening will be disposed within the intermediate gasket space and outer opening will be configured to be connected to a pressure source.

The channel connecting the intermediate gasket space with the surroundings maypreferably be arranged toward the area (A) surrounded by the gasket. Alternatively, the channel may be arranged away from the area (A) surrounded by the gasket.

The first element is advantageously a filter frame of an air filter and the second elementis a filter mounting structure of an air filter housing, and the gasket is then suitably configuredto have a size and shape adapted to fit the gap between the filter frame and the mounting structure.

The sealing device can be included in an air filtration apparatus comprising the sealingdevice, a filter frame, and a filter housing, and wherein the sealing device is located in a gapbetween the filter frame and the filter housing so that the gasket members ofthe sealing deviceare in contact with the filter frame and the housing. The air filtration system can comprise anair filtration apparatus and a pressure source, which is connected to the intermediate space(s)of the sealing device, to allow the pressure source to maintain a set pressure difference towardsthe surroundings. The air filtration system can also suitably comprise a control sensor locatedbetween the pressure source and the surroundings, which control sensor is preferably configured to communicate with an evaluation device. 9 A method of installing the above sealing device in an air filtration system may comprisethe steps of positioning the sealing device in the gap between the filter frame and the filterhousing; mounting the filter frame to the housing so that the gasket members of the sealingdevice are in contact with the filter frame and the housing; and connecting the channel to thepressure source to allow a pressure to be applied on the intermediate gasket space(s) of the sealing device.

As mentioned above the sealing device is configured to be connected to a pressuresource adapted to apply a pressure on the intermediate gasket space. The pressure may be anoverpressure or an underpressure, which means that the pressure is applied by the pressuresource so as to create positive or negative pressure difference relative to the surroundings, i.e.outside ofthe intermediate gasket space. The pressure can suitably be applied by the pressuresource such that the pressure difference between the intermediate gasket space and the surrounding is 50 Pa-1000 kPa, preferably 1 kPa-500 kPa.

As the gasket is comprised of two separate elongated gasket members, the intermediategasket space is open toward the surfaces ofthe first and second elements, the application of apressure to the intermediate gasket space will have the effect that ifa leak should arise on eitherside ofthe gasket, the pressure within the intermediate gasket space will be affected, such as aleakage flow is pushed back if the applied pressure is an overpressure, or sucked into theintermediate gasket space if the applied pressure is an under pressure as compared to the pressure outside the gasket.

The pressure source can preferably be configured to continuously maintain a setpressure difference towards the surroundings to allow continuous improved leak tightness. Thepressure source can be any suitable pressure or vacuum source, such as an air pump or a pressure or vacuum tank, or a centralized compressed air system.

As mentioned above, methods for leakage detection are available, for exampleaccording to the standards ISO 10648-2, EN12237 or EN1886. These methods generally includeapplying a pressure to the interior volume of the sealed enclosure or room to be leak tested,stabilising the pressure and monitoring any changes in the pressure on the volume during a testtime period. A leakage detecting or monitoring device suitably comprises a leakage sensorpositioned in a conduit between the pressure source and the intermediate gasket space. Theleakage sensor is configured to be able to detect a pressure change within the intermediategasket space, which is indicative of leakage. When the pressure source is connected to the intermediate gasket space, leakage detection can be available at all times, and can be applied also while the sealed enclosure or room to be tested is in use or operation. Thus, the leakagedetection can be applied on the actual equipment to be used, including the seal of the gapduring service. No substitute parts, such as blanking plates or the like, need to be used. Theleakage sensor can be selected in accordance with the leak tightness requirement set for thesealed enclosure or room, to be able to detect unacceptable leaks. lt can be an air flow sensoror a pressure sensor, for example a thermal airflow sensor, pressure drop measurement devicefor measurement over capillaries or orifices, rotating vane, vortex meter, or ultrasonic flowmeter. The leakage monitoring device can further comprise a control sensor located betweenthe pressure source and the surroundings, to allow to monitor that the pressure source isoperating properly. The control sensor can be selected from the same types as the leakage SQHSOF.

The leakage sensor can be configured to communicate with an evaluation device, suchas a computer, to allow remote surveillance of the leakage monitoring. For example the sensorcan include a transmitter for wireless communication with a receiver, or the communication canoccur via wired connection. The leakage monitoring device further adva ntageously comprises abackup pressure source arranged parallel to the pressure source, to minimize the risk ofpressure failure. I\/|onitoring may preferably be performed continuously by continuouslyapplying pressure to the intermediate gasket space by means of the pressure source, andcontinuously obtaining the leakage detection values from a leakage sensor, and optionally alsofrom a control sensor, and continuously comparing the leakage detection values with setpointvalues. By continuously monitoring the leak tightness of the gap sealed by the sealingarrangement, a leak can be immediately detected, and accordingly no backtracking to an earlierleak tightness validation is needed. ln the manufacture of products sensitive to contamination,such as pharmaceuticals, the process batch currently being produced when a leak is detectedcan be identified and be tagged to be checked or disposed of. This can lead to less waste, sinceonly the tagged batch needs to be checked or disposed of, contrary to traditional intermittentleak tightness validation where all batches produced since the last successful validation may be compromised.

DESCRIPTION OF El\/lBODll\/IENTS SHOWN IN THE DRAWINGS The subject-matter ofthe present disclosure will now be described with reference to theaccompanying drawings, in which non-limiting example embodiments of the disclosure are shown. The subject-matter may, however, be embodied in other forms and should not be 11 construed as limited to the herein disclosed embodiments. The disclosed embodiments are provided to fully convey the scope of the disclosure to the skilled person.

Figs. la and lb schematically illustrate a sealing device 1 comprising a gasket 5configured to seal a gap 2 between a first element 3 and a second element 4. As shown in thedrawing, the gasket is arranged to be located in the gap 2 and to be in contact with the first andthe second elements during use. The gasket 5 comprises two elongated gasket members: aninner elongated gasket member 5a configured to surround an area A (not shown in Fig. 1) andan outer elongated gasket member 5b configured to surround the inner gasket 5a and the areaA. Figs. 4a and 5a show examples of how the elongated gasket members surround the area A.The sealing device includes a carrier member 6, which extends along the length of the elongatedgasket members, and to which the gasket members are attached to be held in position on adistance from each other so that an intermediate gasket space 8 is formed between them. Achannel 7 connects the intermediate gasket space 8 with the surroundings, in the example ofFig. la arranged through the gasket member 5a, and in the example of Fig. lb through thegasket member 5b. When the channel 7 is arranged through the inner gasket member 5a, thechannel will connect the intermediate gasket space with the side of the sealing device that issurrounded by the gasket, and when the channel 7 is arranged through the outer gasketmember 5b, the channel will connect the intermediate gasket space with the side of the sealingdevice that is outside area surrounded by the gasket. ln the following, the embodiments areillustrated with the channel directed toward the area surrounded by the gasket. However, allthese embodiments may apply also to variants where the channel 7 is directed away from thearea surrounded by the gasket. The channel is configured to be connected to a pressure source,to allow application of pressure on the intermediate gasket space 8 during use, as illustrated in Fig. 7.

Figs. 2a-c, 3, 4a and 4b schematically illustrate embodiments wherein the carriermember 6 is a frame 6a. The frame has a first surface 9' and a second surface 9", opposite toone another and extending between the two elongated gasket members. Thereby a firstintermediate gasket space 8' is partially confined by said first surface 9', and a secondintermediate gasket space 8” is partially confined by said second surface 9". ln theseembodiments the two elongated gasket members 5a,5b are divided along their length, into anfirst gasket member portion 5a', 5b' and a second gasket member portion 5a",5b", with the firstgasket member portions 5a', 5b' attached to the first surface 9' of the frame, and the secondgasket member portions 5a", 5b" attached to the second surface 9" of the frame 6. As shown the frame can be made to extend beyond the gasket member portions in a direction transverse 12 to the length of the elongated gasket members so that it is exposed on the outside of the gasket.ln the embodiments shown in Figs. 2a-c, the carrier member is in the form of a solid frame. lnFig. 2a, the channel 7 is formed through the solid frame, in the form of a through bore. ln Fig.2b, the carrier member is a continuous frame with no openings between the two intermediategasket spaces formed on each side of the frame. Channels 7 are arranged through the gasketmembers on both sides of the frame to connect the two intermediate gasket spaces with thesurroundings. ln Fig. 2c, the carrier member is solid, but has an opening connecting the twointermediate gasket spaces, so that they can both be connected with the surroundings by meansof a channel through one of the gasket members. The intermediate gasket spaces are thusconnected each of the intermediate gasket spaces 8', 8" with the surroundings and being configured to be connected to a pressure source is arranged through the frame 6a.

Also, in the example shown in Figs. 4a and 4b, carrier is in the form of a solid frame 6a.The channel 7 connecting the intermediate gasket spaces 8 on each side of the frame is directed toward the surrounded area A. ln the example shown in Fig. 3, the carrier member is in the form of a frame having ahollow structure, where inner openings 10 are arranged in the first and second surfaces 9',9"and an outer opening 11 is arranged in a portion of the frame extending beyond the first andsecond gasket member portions so that the outer opening 11 can be connected to a pressuresource. ln this case, the frame in its entirety acts as a channel connecting the intermediate gasket spaces with the surrounding.

Figs. 5a and 5b schematically illustrate an embodiment wherein the carrier member 6 isan open framework 6b extending between the elongated gasket members. The carrier memberis not shown in Fig. 5a. ln Fig. 5b the illustrated carrier member is a zig zag structure, and thetwo elongated gasket members 5a, 5b are attached to the carrier member so that portions ofthe open framework 6b are partially enclosed by the material of the two elongated gasketmembers 5a, 5b. The channel 7 connecting the intermediate gasket space 8', 8" with thesurroundings and being configured to be connected to a pressure source is arranged through one ofthe two elongated gasket members.

Figure 6 illustrates how the sealing device 1 can be mounted between a filter 23 (first element 3) and a filter housing 24 (second element 4) in an air filtration apparatus, so as to seal 13 the gap 2 between the filter frame and the filter housing. Thus, in this case the area surrounded by the elongated gasket members will be the surface ofthe filter.

Figure 7 shows schematically a leak tightness monitoring system, where a pressuresource is connected to the intermediate gasket space (not shown in Fig. 7) via the channel 7. Apressure source 14 is adapted to apply a pressure on the intermediate gasket space 8. Thepressure source is arranged in fluid communication with the intermediate gasket space 8between the gasket members via a conduit 12. A leakage monitoring device 9 is included in thesealing arrangement and comprises a leakage sensor 13 positioned in the conduit 12 betweenthe pressure source and the intermediate gasket space 8. The leakage monitoring device mayfurther comprise a control sensor 16 located between the pressure source and thesurroundings. The leakage sensor 13 comprises a transmitter configured to communicate withan evaluation device 17, which comprises a receiver to receive information from the leakagesensor or the control sensor. A backup pressure source 18 can be arranged parallel to the pressure source 14.

The person skilled in the art realizes that the present disclosure is not limited to thepreferred embodiments described above. The person skilled in the art further realizes thatmodifications and variations are possible within the scope ofthe appended claims. Additionally,variations to the disclosed embodiments can be understood and effected by the skilled personin practicing the claimed disclosure, from a study of the drawings, the disclosure, and the appended claims.

Claims

1. A sealing device (1) comprising a gasket (5) configured to seal a gap (2) between a firstelement (3) and a second element (4), wherein the sealing device is arranged to be located inthe gap (2) and to be in contact with the first and the second elements (3,4) during use, characterised in that the sealing device comprises - a gasket (5) comprising two elongated gasket members (5a, 5b), where an innerelongated gasket member (5a) is configured to surround an area (A), and anouter elongated gasket member (5b) is configured to surround the inner gasket(5a) and said area (A), and - a carrier member (6), extending along the length of the elongated gasketmembers (5a,5b) , and said elongated gasket members (5a,5b) being attached tothe carrier member so that they are held in position on a distance from eachother so as to form an intermediate gasket space (8) between the gasketmembers (5a,5b); and - a channel (7) connecting the intermediate gasket space (8) with the surroundingsand being configured to be connected to a pressure source, to allow application of pressure on the intermediate gasket space (8) during use.

2. The sealing device of claim 1, wherein the carrier member (6) is a frame (6a) having a firstsurface (9') and a second surface (9"), said second surface (9") being opposite to said firstsurface (9'), and said first and second surfaces extending between the two elongated gasketmembers (5a,5b), whereby a first intermediate gasket space (8') is partially confined by said firstsurface (9'), and a second intermediate gasket space (8") is partially confined by said second surface (9").

3. The sealing device of claim 2, wherein at least one ofthe two elongated gasket members (5a,5b) is divided along its length, into an first gasket member portion (5a', 5b') and a second gasketmember portion (5a", 5b"), wherein the first gasket member portion(s) (5a', 5b') is/are attachedto the first surface (9') of the frame, and the second gasket member portion(s) (5a", 5b") is/areattached to the second surface (9") ofthe frame (6), and wherein the frame extends beyond atleast one pair of said first and second gasket member portions (5a', 5b'; 5a", 5b") in a direction transverse to the length ofthe elongated gasket members (5a, 5b).

4. The sealing device of claim 1, wherein the carrier member (6) is an open framework (6b)extending between the elongated gasket members, and wherein the two elongated gasketmembers (5a,5b) are attached to the carrier member so that portions of the open framework (6b) are partially enclosed by the material of the two elongated gasket members (5a,5b).

5. The sealing device of any one of claims 1-4, wherein the channel (7) connecting theintermediate gasket space (8', 8") with the surroundings and being configured to be connectedto a pressure source is arranged through one ofthe two elongated gasket members (5a,5b; 5a', 5b'; 5a”, 5b").

6. The sealing device of claim 2 or 3, wherein the channel (7) connecting the intermediate gasketspace (8', 8") with the surroundings and being configured to be connected to a pressure source is arranged through the frame (6a).

7. The sealing device of claim 6, wherein the frame (6a) is a ho||ow structure having one or moreinner openings (10) arranged in said first and/or second surface (9', 9") and an outer opening(11) arranged in a portion of the frame extending beyond the first and second gasket memberportions (5a', 5b'; 5a", 5b"), said outer opening (11) being configured to be connected to a pFeSSUFe SOUFCQ.

8. The sealing device of any one of claims 1-7, wherein the channel (7) connecting theintermediate gasket space (8', 8") with the surroundings is arranged toward the area (A) surrounded by the gasket.

9. The sealing device of any one of claims 1-7, wherein the channel (7) connecting theintermediate gasket space (8', 8") with the surroundings is arranged away from the area (A) surrounded by the gasket.

10. The sealing device of any one of claims 1-9, wherein said first element is a filter frame of anair filter (23) and said second element is a filter mounting structure of an air filter housing (24),and the gasket is configured to have a size and shape adapted to fit the gap between the filter frame and the mounting structure.

11. An air filtration apparatus comprising the sealing device (1) of claims 1-10, a filter frame (23)of an air filter, and a filter housing (24) including a mounting structure, wherein the sealingdevice is located in a gap (2) between the filter frame and the mounting structure of the filterhousing so that the gasket members of the sealing device are in contact with the filter frame and the mounting structure ofthe filter housing.

12. An air filtration system comprising an apparatus according to claim 11 and a pressure source(14), which is connected to the intermediate space(s) ofthe sealing device, said pressure source preferably being configured to maintain a set pressure difference towards the surroundings.

13. The air filtration system of claim 12, further comprising a control sensor (16) locatedbetween the pressure source and the surroundings, said control sensor (16) preferably being configured to communicate with an evaluation device (17).

14. A method of installing the sealing device (1) of claims 1-10 in the air filtration system of claim12-13 comprising the steps of: - positioning the sealing device (1) in the gap (2) between the filter frame (23) and themounting structure ofthe filter housing (24); - mounting the filter frame to the housing so that the gasket members of the sealingdevice are in contact with the filter frame and the housing, whereby the intermediategasket space becomes confined by the gasket members, a surface ofthe filter frame anda surface of the filter housing; - connecting the channel (7) to the pressure source (14) to allow a pressure to be applied on the intermediate gasket space(s) (8; 8', 8") of the sealing device.